Fig. 3

Discrimination of SLC26A4 gene c.919-2A > G and c.2168A > G variants by Pfu DNA polymerase-mediated phosphorothioate-modified primer extension. M is 50 bp DNA marker; Lanes 1 and 8 is specific primer extension products from the primer of c.919-2A > G site for A allele, Lanes 2 and 7 are specific primer extension products from the primer of c.919-2A > G site for G allele, Lanes 3 and 10 are specific primer extension products from the primer of c.2168A > G site for A allele, Lanes 4 and 9 are specific primer extension products from the primer of c.2168A > G site for G allele, Lanes 5 and 12 are specific primer extension products from primer mixture of c.919-2A > G site for A allele and c.2168A > G site for A allele, Lanes 6 and 11 are specific primer extension products from primer mixture of c.919-2A > G site for G allele and c.2168A > G site for G allele; Lanes 1 to 6 are the PCR products using wild vector as wild template; Lanes 7 to 12 are the PCR products using mutant vector as mutant template. The specific DNA product targeting c.919-2A > G and c.2168A > G loci is 280 bp and 65 bp respectively. Lanes 5, 6, 11 and 12 generate an extra 518 bp nonspecific fragment from a pair of amplification primers consisting of the forward detection primer of c.919-2A > G and the reverse detection primer of c.2168A > G